package puziran.sofa.util;

import java.io.UnsupportedEncodingException;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;

public class MD5
{
  private static final char[] DIGITS = { '0', '1', '2', '3', '4', '5', '6', 
    '7', '8', '9', 'a', 'b', 'c', 'd', 'e', 'f' };

  public static String md5(String text, String charsetName)
  {
    MessageDigest msgDigest = null;
    try {
      msgDigest = MessageDigest.getInstance("MD5");
    } catch (NoSuchAlgorithmException e) {
      throw new IllegalStateException(
        "System doesn't support MD5 algorithm.");
    }
    try {
      if (charsetName == null)
        msgDigest.update(text.getBytes());
      else
        msgDigest.update(text.getBytes(charsetName));
    }
    catch (UnsupportedEncodingException e) {
      throw new IllegalStateException(
        "System doesn't support your  EncodingException.");
    }

    byte[] bytes = msgDigest.digest();
    String md5Str = new String(encodeHex(bytes));
    return md5Str;
  }

  public static String md5(String text)
  {
    return md5(text, null);
  }

  private static char[] encodeHex(byte[] data) {
    int l = data.length;
    char[] out = new char[l << 1];
    int i = 0; for (int j = 0; i < l; i++) {
      out[(j++)] = DIGITS[((0xF0 & data[i]) >>> 4)];
      out[(j++)] = DIGITS[(0xF & data[i])];
    }
    return out;
  }

  public static void main(String[] args) {
    System.out.println(md5("123456"));
  }
}